Car-retarding apparatus



Dec. 24, 1963 c. M. ANDERSON CAR-RETARDING APPARATUS 9 Sheets-Sheet 1 Filed June 7, 1962 r1111 1 \1 1 1L 11 1 111111 1 .1 w

INVENTOR CHARLES M. ANDERSON BY w M ATTORNEY Dec. 24, 1963 c. M. ANDERSON CAR-RETARDING APPARATUS 9 Sheets-Sheet 5 Filed June 7, 1962 INVENTOR CHARLES M. ANDERSON w? ATTORNEY 1 Dec. 24, 1963 c, Rsou 3,115,215

CAR-RETARDING APPARATUS Filed June 7, 1962 9 Sheets-Sheet 5 CHARLES M. ANDERSON BY 60E,

ATTORNEY Dec. 24, 1963 c. M. ANDERSON 3,

CAR-RETARDING APPARATUS Filed June '7, 1962 9 Sheets-Sheet 6 INVENTOR CHARLES M ANDERSON BY SAD/UM ATTORNEY Dec. .24, 1963 c. M. ANDERSON 3,115,215

CAR-RETARDING APPARATUS w UL-l h 2 V i INVENTOR CHARLES M AN DERSON BY M0771 ATTORNEY DecQ24, 1963 c. M. ANDERSON CAR-RETARDING APPARATUS 9 Sheets-Sheet 8 Filed June 7; 1962 INVENTOR CHARLES M. ANDER5ON O ATTORNEY Dec. 24, 1963 c, M. ANDERSON 3,115,215

CAR-RETARDING APPARATUS Filed June 7, 1962 9 SheetsSheet 9 a i. r' 8- z I03 i :44

I 2 g 37 v 124 I39 I (40 136 I4, I42

V s O C '44 4n n j y INVENTOR CHARLES M. ANDERSON ATTORNEY United States Patent 3,115,215 AR=RETARDENG APPARATUS Charles M. Anderson, Paris, K32, assignor to The; W. R. Stamler Corporation, Paris, Ky, a corporation of Kentuchy Filed June '7, 1962, er. No. 2%,680 10 Claims. (Cl. 18863) This invention relates to car-retarding apparatus and more particularly to apparatus of the type wherein the movement of the car being retarded is controlled by the regulated flow of a fluid which is under a pressure exerted by the retarded lo-ad.

Various forms of such retarding apparatus have been employed but, in general, have been characterized by complicated means for governing the flow of fluid in the fluid system associated with the mechanical portion of the apparatus, and by complicated mechanical movements for raising and lowering the dogs which serve to retard the moving cars. It is a purpose of my invention to provide a car-retarding apparatus which is less complicated than those found in the prior art but Without sacrifice of safety or adaptability to handling of various loadings. U

One object of the invention is to provide an improved dog-actuating slide for car-retarding apparatus.

Another object is to provide an improved dog construction for use with car-retarding apparatus.

Another object is to provide a simplified fluid pressure system for car-retarding apparatus.

Another object is to provide an improved electrical system actuated by the movable portions of the mechanical car-retarding structure and governing valves arranged in the fluid pressure system which permits the movement of those mechanical portions.

A hird er object is to provide a longitudinally compact car-retarding apparatus having a pair of fluid motors, the stroke of the moving elements of which are readily adjustable.

The foregoing and other objects and advantages of the invention will be more clearly understood by reference to the following description and to the accompanying drawings, in which:

FIG. 1 is a diagrammatic View illustrating the relation of the retarder apparatus to a trip of cars.

FIG. 2 is a plan view of one portion of the retarder apparatus showing the right hand elongated fluid motor approaching. its extreme of forward movement.

FIG. 2A is a complementary view of the structure shown in FIG. 2.

FIG. 3 is a sectional view taken on line 3-3 of FIG. 2 and to a larger scale.

FIG. 4 is a side elevation view of the dog-actuating slide.

PEG. 4A is a view of the slide taken on line 4A-4A of 1:16. 4.

FIG. 4B is a view of the slide taken on line 4B4B of FIG. 4.

PEG. 5 is a plan view of the right hand fluid motor cylinder equipped with its barney, dog, and dog-actuating slide, and with the parts shown in the position occupied when the cylinder has reached its rearmost position.

FIG. 5A is a sectional view to a larger scale taken on line 5A 5A of FIG. 5.

FIG. 6 is a side elevation of the equipped cylinder shown in FlG.

FiG. 6A is an elevation view to 'a larger scale showing the bracket for mounting the dog-raising spring.

FIG. 7 is a sectional view to a larger scale taken on line 7-7 of FIG. 6.

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FIG. 8 is a side elevation view of the right handdog.

FIG. 9 is a plan view of the dog shown in FIG. 8.

PEG. 10 is a diagrammatic view of a portion of a suitable fluid pressure system for carrying out the invention, conventional J.I.C hydraulic symbols being shown.

FIG. 10A is a diagrammatic view of the remaining portion of the system shown in FIG. 10.

FIG. 11 is an across-the-line diagram of an electrical system suitable for employment with the invention, the switches being shown in the position occupied by the apparatus :as shown in FIG. 2.

FIG. 12 is a view similar to FIG. 11 and showing the switches in the position occupied at the end of the overtravel of the right-hand retarding assembly.

In accordance with the invention, a pair of similar elongated fluid motors comprising a right-hand unit and a left hand unit (as viewed in the direction of trip travel of cars being retarded) are mounted upon a framework disposed between the rails on which the cars are adapted to travel. Each of these motors includes a barney structure mounting a pivoted retarding dog which at appropriate times is moved into its car-engaging position and thereafter is moved into its car-disengaging position after its companion dog is in position to take over the retarding action. The movement of these dogs is effected by simple mechanical means actuated in dependence upon the movement of the movable portions of the motors. A fluid pressure system is provided and includes an overtravel fluid motor serving to pull the dog of one barney ahead of the car during movement of that dog to its car-disengaging position and while its companion dog is retarding the load. Associated with the overtravel motor is a cable interconnecting the movable portions of the two elongated motors, and included in the flu d pressure system are a pressure fluid source, conduit means interconnecting the two elongated fluid motors, a transfer valve for actuating the overtravel motor, a vent ing valve for permitting the elongated motors to vent rapidily at the conclusion of a retarding stroke, and means for replenishing the fluid system and for placing pilot pressure on the appropriate valves. A simple mechanical shift rod actuated in dependence upon the movement of the movable portions of the elongated fluid motors in turn actuates electrical switches which then establish circuits through solenoids associated with the transfer and venting valves and thus effect the shifting of those valves at appropriate times. In general, the invention is intended to employ a simplified fluid pressure system, with a reduction in the number of valves, connecting fluid conduits and the like, when contrasted with conventional retarding apparatus.

Referring first to FIG. 1 a trip of interconnected cars ill, 11 having car-hauls 12 and 13 thereon, is adapted to move along rails, one of which is seen at 14, and to pass over a framework generally indicated 15 and lying between the track rails. Retarding dogs 16 and 17 associated respectively with the left hand and right hand retarding fluid motors, later to be described, are positioned for engagement with the car hauls 12 and 13. As will later be apparent, the invention provides for rapid movement of these dogs away from the car hauls when they are to be disengaged and as seen with respect to the dotted line position 17A, that particular dog may rapidly move forwardly through the distance 18 when the apparatus occupies the positions shown in FIGS. 2 and 2A, and now to be described. As an example of one satisfactory usage, the distance 18 corresponding to the overtravel, as will later appear, may be in order of twelve inches, and it will be understood that when the dog 16 in turn reaches the position indicated by 17 in FIG. 1, it, too, will move rapidly through the distance 13 in order to become disengaged from its load.

FIGS. 2 and 2A and 3, the framework 15 may comprise a rigid assembly of a pair of parallel channel members it and 21 spaced from each other and joined at their rear ends by a transverse plate 22 which supports a pair of adjustable rods or strike members 23 and 24, the longitudinal positioning of which determines the length of rearward stroke of the fluid motors. As used herein, the terms rear and forward are related to the direction of trip travel. At their forward ends the channel members are joined by a transverse member 25 having a central fiat portion 26 serving as a support for slide plate 27 and upon which a rotatable sheave 28 is mounted. Rearwardly of the fixed member 25 a fixed, massive abutment member 29 rigidly joins the channel members and supports a pair of adjustable strike members 39 and 31, the longitudinal positioning of which determines the length of forward stroke of the fluid motors. A central longitudinal inverted T-shaped member 49 arranged parallel to the channel members and located midway therebetween and fastened to plate 22 and to abutment 29, also forms part of the framework. Additional cross members joining the channel members adjacent the bottoms of those channel members may be used as needed for structural strength of the framework.

Mounted upon the framework is a pair of elongated fluid motors extending lengthwise in parallel relation to each other. Various forms of such motors may be employed with my invention, but I prefer to use a single-acting type having the cylinder serving as the movable portion of the motor and in order to provide a longitudinally compact assembly, to have the cylinders staggered in overlapping relation at all times. As best shown in FIG. 2, a preferred arrangement includes reaction rods 32 and 33 mounted upon abutment 29 and with fluid passages 34 and 35 extending completely therethrough and in communication through the plugs 36 and 37 at their rear ends with the interiors of the movable cylinders 38 and 39, respectively. Each of the cylinders is closed at its rear end by a cylinder head 40 and 41 respectively, and car- 'ries at its forward end an apertured plate 42 and 43 respectively, slidable along the corresponding fixed reaction rod.

At their forward ends the reaction rods are suitably mounted within the fixed abutment 29, and in fluid communication with the passages 34 and 35 of those rods are conduits 44 and 45, respectively, leading to a pressure fluid system later to be described. Rigidly attached to and extending between the cylinder heads and forward end plates of the cylinder are vertically disposed flat side plates t) and 51 respectively, these side plates being disposed adjacent the central member 49 of the framework. Attached to the sides of member 49 are elongated hardened guide rails 52 and 53 and attached to the respective inner sides of the channel members 20 and 21 are similar rails 54 and 55. Adjacent the midlength of each of the cylinders 38 and 39, and rigidly mounted on the side thereof nearest the channel members of the framework, are fixed shoes 56 and 57 adapted to slide along the rails 54 and 55 respectively, and to serve as shift rod actuators. Moreover, adjacent the ends of each of those cylinders and pivotally mounted upon the respective side plates 50 and 51 are pairs of shoes 53, 59 and 6t), 61 adapted to ride along the respective rails 52 and 53. Additional wear pads or shoes attached to the cylinders may be used as desired, but in general, the above described fixed and pivotable shoes are sufiicient to insure a properly guided reciprocable movement for the cylinders.

Referring now to FIG. 4, the invention comprehends the use of a dog-actuating slide member carried by each of the cylinders for operating the dog associated with that cylinder, and such a slide member for the right hand dog may comprise a pair of plate sections 65 and 66 attached side-by-side to each other and with the section es having a rearwardly facing cam surface 67. Bolted or otherwise secured to the forward top edge of section 6t? is an elon- Passing now to gated dog-lowering rod 68 of non-circular cross section terminating in a pad 69 adapted to contact the confronting end of the stroke adjusting strike member 31. Bolted or otherwise secured to the rearward top edge of section 66, and offset both laterally and vertically from the rod 68 is an elongated dog-raising rod 755 of non-circular cross section terminating in a pad 71 adapted to contact the confronting end of the stroke adjusting strike member 24-. Suitable apertures are provided in each of the cylinder head it? and the plate 42 at the opposite end of cylinder 33 to receive the respective rods 7t? and 68 and to permit guided movement of the same therethrough. In like manner, the slide member for the left hand cylinder and dog includes a dog-lowering rod 63A with pad 69A adapted to Contact stroke adjusting strike member 30 and a dog-raising rod 70A with pad 71A adapted to contact stroke adjusting strike member 23, as seen in FIGS. 2 and 2A. However, as a feature of the invention, the dog-lowering rod 68 is appreciably shorter than its corresponding rod 68A, and the dog-raising rod 7%) is appreciably longer than its corresponding rod 79A, the location of the barney on the respective cylinders, as now to be described, serving to provide for this characteristic of the apparatus.

Considering now FIGS. 5 to 9, the right hand cylinder 38 adjacent and rearwardly of its forward shoe 58 carries a barney member 75 rigidly attached to the side plate 5%) and positioned between that side plate and the central member 49 of the framework. This barney is provided with an upwardly and rearwardly facing generally semicylindrical seat 76 adapted to receive the corresponding arcuate back face 77 of the dog 17 (FIGS. 8 and 9) and to furnish a large contact area for that dog. As seen in FIGS. 8 and 9, the dog comprises a plate 78 of lateral width generally equal to the lateral width of the barney member and having a tip portion 79 of hardened metal thereon, adapted to contact the car hauls. Attached to the inner side of plate 78 by means of a spacer plate $9 is a dog-actuating plate 81 extending to a lower elevation, as best shown in FIG. 8. The upper edge of the side plate 59 for the cylinder, moreover, is cut away to receive the spacer plate as the dog moves upwardly and downwardly, and through this side plate an aperture is provided to receive a pin 82 (FIG. 5) passing through holes 83 and 34 in the respective plates 78 and 81 (FIG. 9) and serving to mount the dog upon the barney. Due to the direc tion of retarding forces upon the dog and to the large contact surface between the barney and the plate 78, a comparatively small diameter pin 82 may be used since shearing stresses are relatively small.

At its forward and lower end the dog-actuating plate 81 includes a forwardly facing recess $5 into which one end of a guide rod 85A cooperating with a heavy compression spring 86, engages; the other end of that spring being retained against a bracket 87 located on the inner side of the side plate 50 of the cylinder 38 (FIGS. 6A. and 7). This recess is substantially below the pivotal axis of the dog at pin 82 with the result that the dog is biased toward a first, or car-engaging position in which its tip portion 79 is raised. As a significant feature of the construction, the plate 81 carries adjacent its lower and rearward end a laterally projecting pin 33 upon which a roller 89 is mounted and these parts are located in the same vertical plane as the cam surface 67 of the slide member, and in the path thereof as it is moved in dependence upon the movement of cylinder 38. Since the plates 78 and 31 of the dog straddle the upper edge of side plate 59, no lateral shifting of the dog can occur and movement of the dog is restricted to oscillation about the axis of pin. 82. Whereas, only the right hand dog 17 has been de-- scribed, it will be understood that the left hand dog 16 associated with cylinder 39 is of a similar construction and is arranged for cooperation with the dog actuating slide member carried by that cylinder. As shown in FIGS. 5 to 7, the mounting of the slide members preferably includes guiding means interntediate the extreme ends of the cylinder and their guiding means may further serve as reinforcement for the side plate 5%. For example, cover plates 9%, 91 and 92 may be welded to both the upper edge of the side plate 51) and to a lateral upper part of the cylinder 38 and serveto shield the movable dog-actuating slide against foreign objects falling thereon. Also a bridge member 93 (FIG. 5A) may extend between that side wall and cylinder to serve as a support along which the elongated dog-raising rod 70 may slide. For ease in assembling or disassembling the dog-actuating slide, a removable cover plate 94 (FIG. 7) attached by screws to strips 95 and 96 which in turn are affixed to the undersurface of the fixed cover 99 is provided. When this removable cover is raised, the dog lowering rod 68 may be detached from the above-described plate 66 of the slide. The strips 95 and 96 also serve to guide the rod 68 in its longitudinal sliding movement. A similar arrangement for guiding the left-hand slide assembly associated with cylinder 39 is provided.

Referring now to FIGS. 2 and 2A, an elongated shift rod 98 is slidably mounted within the channel portion of channel member 20* and carries at its forward end a switch actuating pad 99. Adjustably attached to this shift rod at suitably spaced distances and extending through slots in the channel member into the path of the cylinder shoe 56 are pins we and 101. Accordingly, as cylinder 38 moves forward, the leading edge of shoe 56 engages pin 1% and carries the shift rod forwardly and as the cylinder moves rearwardly the other edge of the shoe will in due time engage the pin 101 and carry the shift rod to the rear, a lost motion thus being present which requires the shift rod to shuttle intermittently through only a short distance. Mounted upon the framework at appropriate locations for actuation by the pad 99 is a pair of switches 102 and 103 having pivoted arms extending into the path of travel of that pad and being of a type later to be described.

Similarly associated with the left hand cylinder is a shift rod 98A having an actuating pad 99A for coaction with switches 162A and 103A, the rod being shifted by engagement of shoe 57 with pins 160A and 101A.

As best seen in FIG. 2, the plates 42 and 43 at the forward ends of the cylinders and which are guided along the hollow stationary reaction posts 34 and 35, are provided with pintles 11% and Ill into which the respective ends of a flexible cable 112 may be securely attached. This cable is trained over the sheave 28 with the result that a movement of one of the cylinders in a rearward direction while filled with fluid under pressure will mechanically urge the other cylinder to travel in the opposite direction, as will later appear. Sheave 28, however, is mounted upon a slidable plate 27 and to an extension of this plate the piston rod 114 and piston 115 of an overtr-avel cylinder 116 is attached, the other end of the cylinder being suitably attached as by a rod 117 to the rigid abutment 29 of the framework. As shown in FIG. A, the cylinder is single-acting, having a conduit 11% through which fluid enters and leaves. Leakage of fluid around the piston is vented through a conduit 119 and to a reservoir 12% of the fluid system later to be described.

Referring now to FIGS. 11 and 12, the switches 10% and l3 A herein called safety switches and the switches 162 and ldZA herein called transfer switches are mounted upon the framework at suitable fixed locations and are provided with arms pivoted for driven movement in one direction and loosely projecting into the path of movement of the pads upon the shift rods. These switches may be of any suitable conventional single-pole, double-throw type capable of functioning in the manner now to be described, one form which is satisfactory being the Snap Lock Limit Switch type SL manufactured by the National Acme Company of Cleveland, Ohio. The operation of these switches in the electrical circuitry and as related to the mechanical movement of the shift rods 98 and 9-A which are moved as the res-pective right hand and left hand cylinders 38 and 39 approach the limits of their paths of movement, may be briefly explained as follows. For example, as seen in FIG. 11 when the right hand cylinder shifts its rod as forwardly in preparation for disengagement of its dog with the trip of cars, a circuit is made from line 121 through closed switch 122, conductors 123, 124, safety switch iii-3A which simultaneously is being held in closed position upon its alternate contacts against the bias of its spring by the pressure of pad 99A attached to shift rod 98A corresponding to the retracted cylinder 39, conductor 125, transfer switch 1S2 which is then closed upon its alternate contacts against the bias of its spring, conductors 12d and 1.27, solenoid coil 12% for a pilot valve 129 (later to be described), and conductor 13ft to return line 131.

Simultaneously, a shunt circuit is established from conductor i126, conductor 13%, the transfer switch 162A resting upon its normal contact under bias of its spring, conductor 133, solenoid coil 134 of pilot valve 135 which controls the positioning of a venting valve 175 (later to be described), and conductors 136 and 137 to return line 131.

It will be further understood that switch 122, which may be manually operated, remains closed at all times during the intended period of operation of the car-retarding apparatus and that closing thereof establishes a circuit from conductor 123, through conductor 13%, solenoid coil 139 of switch 1% and conductor Mil to return line 131. Energization of solenoid 139 and closing of switch l t-ti causes a circuit from line 1231 through the closed switch Mt and motor 142 to the return line 131.

The above described circuits through the solenoids 128 and 134 are maintained so long as cylinder 33 is moving forward with its shift rod pad $9 closing the transfer switch N2. However, as soon as the cylinder 38 has moved sufficiently far forward (and corresponding to the time at which the overt-navel cylinder 116 has been filled with pressure fluid and the conduit 44 from cylinder 38 has vented through venting valve 175 to the reservoir the pad 9 9 rides past the arm of switch M2, which then moves to its normal position, as seen in FIG. 12, but with the co-acting safety switch 1533A of the companion cylinder 39, however, remaining in its closed position upon its alternate contacts against the bias of its spring. When this occurs, the circuits to solenoids 128 and 1-34 are broken and due to the toggle action of the arm of switch W2 will remain broken as the shift rod 98 and its pad 9 are thereafter moved to the rear to close safety switch 1% upon its alternate contacts against the bias of the spring.

Conversely, when the pad WA of shift rod 9$A associated with the left hand cylinder 39 moves forward to close the transfer switch ltlZA upon its alternate contacts, the pad 99 of shift rod 9% simultaneously closing safety switch 1% upon its alternate contacts, a circuit will be made from conductor 123, conductor 14-3, safety switch 193, conductors 144-, MS, transfer switch Hi2, which then is closed by its spring bias on its normal contacts (as in FIG. 12), conductor 146, solenoid coil i of pilot valve acting in opposition to the previously mentioned solenoid coil 134 associated with the same pilot valve, and conductor 137 to return line 3181. Simultaneously, a shunt circuit wi l be made from conductor 144, conductor Md, the switch 192A now being held ipon its alternate contacts, by the pad 99A, conductor i 29, solenoid coil 1.28 and conductor 13% to return line 131. Moreover, when the left hand cylinder 39 moves the pad 99A sufiiciently far forward to release switch 16 2A (and corresponding to the time at which the overtravel cylinder He again has been filled with pressure fluid and the conduit 45 from cylinder 38 has been vented through venting valve to the reservoir 126'), the solenoid coils 123 and 147 will be de-energized as described above with respect to the extreme forward movement of the shift rod cylinder.

With the preceding description of the mechanical and electrical portions of the apparatus in mind, reference now is made to FlGS. 10 and 16A showing one form of pressure fluid system suitable for use in carrying out the: invention. Motor 142 drives a suitable pump 143 which draws a hydraulic fluid from reservoir 1219 through conduit 151} and supplies it under pressure into main conduit 151. Branch conduit 152 is connected between conduit 151 and a suitable relief valve 153 which spills into the reservoir. The main conduit 151 extends to a conventional spring offset, pilot operated 4-way valve 154 (such as Vicke rs type C4420 valve) one outlet line 155 of wmch connects with the conduit 113 extending to the overtravel cylinder 116 and another outlet line 156 of which extends to the combined retarder-cylinder-refilland-pressurization conduit 157. A second relief valve 155 is connected to line 157 by conduit 159' and also spills into the reservoir. As seen in FIG. 10, the transfer valve 154 during inaction of the overtravel cylinder (as when neither of the movable cylinders 38 and 31 has moved sufficiently far forward to actuate its corresponding transfer switch 162 or 1h2A) occupies a position communicating main conduit 151 with its outlet line 156. When, however, the transfer valve is to be shifted, as when the previously described solenoid 12.3 is energized, the energization of that solenoid shifts pilot valve 129 to the right against the bias :of its spring and at this time pilot pressure fluid flows from main conduit 151 through branch conduit 160, through pilot valve 129, conduit 161, and acts upon the piston of transfer valve 154 to shift the same thereby to communicate main conduit 151 with the conduits 155 and 118 leading to: the overtravel cylinder 116. The pilot valve 129 may be of any conventional solenoid operated type (such as Vickers type DG-4S4 012A).

In general, the functioning of the overtravel cylinder 116 in its relation to the action of the trip of cars being retarded may be noted by the following comparison of positions occupied by the several electrical, mechanical and hydraulic elements at the times when the influence of the overtravel cylinder is required. Assuming the system to be operative, it will be understood that switch 122 had previously been closed, that pump motor 142 is operating, that the trip safety valve 1% (later to be described) has been moved to its working position and that one of the dogs of one of the barneys is in contact with one of the car hauls with one of the cars; for example, the dog 17 of barney 7-5 of the right hand cylinder 38 in contact with the car haul 12 of car 111.

At this time, the hydraulic system is permitting recirculation of fluid from the advancing cylinder 38 into the retracting cylinder 39, as later to be explained; the sole noid 128 of the pilot valve 129 is deenergized; and the overtravel cylinder 116 is vented through conduit 118, conduit 155, transfer valve 154 and conduit Zllll. Then as cylinder 38 reaches the point at which the action of the overtravel cylinder is required, the shift rod Q8 reaches the position indicated in PEG. 11 at which time a circuit is made to energize the solenoid coi 128 and the coil 134 of the pilot valve controlling the venting valve 175. As this occurs, the four-way transfer valve 154 shifted to bring conduit 151 into communication with outlet line 155 and pressure fluid is then supplied to the over-travel cylinder 116 through conduit 118. This pushes the piston 115 and the plate 27 carrying sheath 2% in a forwardly direction and serves to pull cylinder 38 rapidly forward and in advance of the car moving overhead, thus permitting the dog 17 to disengage from the car haul 12 and to be lowered. During this increment of forward movement, the cylinder 38 also moves the shift rod 98 a short distance forwardly and out of contact with switch 1%, as seen in FIG. 12.

ssociated with the right hand o u Furthermore, the energizingof coil 134 had served to move the pilot valve 135 for the venting valve 175 so that the fluid in conduit 118 also had acted to shift the venting valve 175 and had permitted a fast venting of the fluid remaining in the right hand cylinder 38 directly into reservoir 121 As a result of this rapid venting the cylinder 38 and its barney and dog were able to move rapidly to the intended disengaged position with respect to the car haul.

When the thus vented cylinder 38 brings its shift rod to the position seen in FIG. 12, solenoids 128 and 147 are deenergized and the transfer valve 154, venting valve 175 and their respective pilot portions 129 and 135 reoccupy their original positions. As this occurs, the overtravel cylinder, which is then filled with pressure fluid, immediately vents through conduit 118, line 155, valve 154- and drain line 2013; and the cable 117 acting in the sheave 28 serves to retract the piston of that cylinder into a position of readiness for the next operation of the \overtravel arrangement. As will be understood, following the above-described overtr-avel cylinder functioning, the left hand cylinder 39 moves forward and the right hand cylinder 38 moves rearwardly, thus causing the shift rod 98 to close safety switch 1% and the shift rod 98A to open safety switch 1113A and later in due time to close transfer switch 1112A.

It will further be understood that after the overtravel cylinder has functioned, as above described with respect to the disengaging travel of the right hand retarder cylinder 28, and the transfer valve again reaches its normal position of FIG. 10, fluid under pressure again flows as required into conduit 157 and thence by connecting conduit 17% to a counter-balance valve 171 which serves as a retarder control valve through which fluid circulating from one retarder cylinder to the other must pass in the manner later to appear. The back pressure upon this valve 171 is kept at a suitable value, for example, about 250 psi. when handling normal retarding loads, and the valve itself may be of a conventional type (such as Vickers type RT06A410). Communicating with the counter-balance valve 171 through conduit 172 is a third pressure relief valve 173 which may be of the same type as the pressure relief valves 153 and 153 (such as Vickers type CT-G6C) but, of course, being set for individual relief pressures. Both valve 171 and valve 173 may vent into the reservoir by connections leading to return line 119.

Considering now the respective conduits 44 and 45 connecting with the single acting cylinders 33 and 39 of the retarder apparatus, conduit 44 connects with a venting conduit 174 leading to venting valve 175 and conduit 45 connects with a venting conduit 176 leading to that same valve. Valve 175 with its pilot section is of a conventional pilot operated, solenoid-controlled, springcentercd, 4-way type (such as Vickers type DG-5S4 062C) and is equipped with the previously described solenoids 134 and 147. With the valve occupying the position shown in FIG. 10, however, no venting into reservoir 1211 from either of the retarder cylinders 38 and 39 can occur and assuming first that the trip safety valve 1% has been moved to its working position and that the right-hand retarder cylinder 33 is moving forward with its dog in retarding contact with the trip of cars, fluid being displaced from that cylinder 33 under pressure of the loading exerted by the cars will pass through recirculating conduit 177 past check valve 178 and into connecting conduit 179 leading both to the pressure relief valve 173 and to the retarder control valve 171. A suitable relief setting for valve 175 may be in the order of about 3000 psi. Also communicating with conduit 179 is an accumulation vessel 13% of conventional construction. The displaced fluid from cylinder 33 after passing through valve 171 is then forced through conduit 17%, conduit 131, past check valve 132, and back into 9 the companion and rearwardly moving rctarder cylinder 39 through the conduit 45.

Conversely, when retarder cylinder 59 is moving forward, fluid displaced into conduit 45 passes through conduit 1 83, past check valve 184, into connecting conduit 179, through the control valve 171, conduits 17b and 185, past check valve 1-85 and back into the companion and rearwardly moving retarde-r cylinder 38 through conduit 44. Meanwhile, regardless of which retarder cylinder is being filled or emptied, refill fluid from the conduit 157 is present to prevent any cavitation in a ret-arder cylinder.

One of the important capabilities of the present invention is its flexibility of use with the retarding of cars moving solely under gravity on inclined tracks of various gradients, or in association with other equipment employed in the controlled movement of the trip of cars, such as carushing or spotting apparatus, automatic loading stations and the like, which also have pressure fiuid systems. The run-away of a trip of cars must be prevented at all costs and in the present system I provide the trip safety valve 1% which may be a conventional spring offset, 4-way valve (such as Vickers type C438), the movement of which to trip advancing position, may be manually or automatically controlled. Normally, the valve 190 occupies the position shown in FIG. and in which no car movement can occur since the counter balance retarder control valve 171 is blocking the above-described recirculation of fluid between cylinders 38 and 39. The same blocking action would occur in the event of an accident such as breaking of a dog-actuating slide, or the rupture of a conduit in the fluid system.

Therefore, when trip advancing movement is intended, valve is moved to bring branch circuit 191, connected to conduit i157, into communication through that valve with conduit '52 leading to control valve 171, at which time the control valve 171 permits the abovedescribed recirculation between the retarder cylinders.

Considering now in greater detail the operation of the electrical system with respect to the fluid system of the apparatus disclosed, and assuming the retarder cylinder 38 to be advancing under load; recirculation of iiuid from cylinder 33 to cylinder 39 continues until the forwardly moving right hand cylinder 38 moves the shift rod as to actuate simultaneously the transfer valve E54 and the venting valve 171?, resulting from the now to be described movement of their associated pilot valves 12?? and 135 by means of the electrical circuit shown in FIG. 11. Accordingly, at this time solenoid 3123 is energized pushing pilot valve 129 to the right against the bias of its spring. This valve movement shifts transfer valve 154 and fluid under pressure is supplied to overtravel cylinder 316. As piston 115 starts to move, the sheave 2? also moves placing tension upon cable slit, but since one end of that cable is attached to cylinder 39, which being filled with fluid cannot move with the cable, the increased tension is exerted upon the other cylinder 38 urging it to move rapidly and to force out any remaining fluid therein so that its dog may be quickly disengaged from the car haul. Concurrently with the energization of solenoid 12$, solenoid 134 is energized and pushes pilot valve 135 to the left, at which time pilot pressurization fluid flows from conduit 118 through conduit 195, through valve 135 and conduit 1% to move venting valve 175 to the left against the bias of its centering springs. When this occurs, communication is established from conduit 174, through valve 175, and conduit 197 to the venting line 1% leading to the reservoir. Pilot fluid from the other side of venting valve 1'75, at this time, bleeds through connecting conduit 1% into vent line -9, which like the vent line 119, joins with line Under these conditions the tension exerted by cable 112 pulls the right hand cylinder 38 quickly forward as the overtravel cylinder 11a fills and since at this time the dog-lowering rod 63 has abutted against fixed strike member 31, the continued movement of cylindcr 38 brings the roller 89 of the dog 17 into contact with the now stationary cam surface 67 of the dogactuating slide and the dog thus is cammed downwardly out of engagement with the car haul. it will be understood that immediately prior to this action, the dograising rod ltlA of the left hand cylinder had contacted the strike member 23 and that as cylinder 39 had continued its rearward movement the roller of its dog had moved forward from the corresponding cam surface of that slide and that its dog had then been raised to carengaging position under action of its spring E56.

As soon as the dog of the right hand cylinder has been lo'-"ered, the pad 99 of the shift rod 98 passes to the pos n seen in FIG. 12 and solenoids 128 and 147 then become deenergized. Each of transfer valve 154, venting valve 175 and their respective pilot portions 129 and 135 then move to their original positions as seen in FIG. 10 and fiuid vents from the overtravel cylinder lllti through conduit M8, line 1555, valve 154 and drain line to reservoir 124i. Meanwhile, the left hand cylinder 39 is starting its forward movement and the loading of the trip of cars is forcing fluid to recirculate into the now retracting cylinder 33. Cylinder 38, moreover, through cable is now pulling the sheave 28 to its retracted p sition and causing piston to push the fluid into conduit Elli for completing the above described venting action.

Eimilarly, when the left hand cylinder moves its shift rod SA to actuate transfer switch 132A and the transfer valve and the venting valve, fluid again is supplied to the overtravel cylinder. in this situation the electrical circuits cause cnergization of the solenoids 123 and 147. The above described fluid fiow circuit for the transfer valve is the same as when the right hand cylinder had moved rod 98, but with respect to the fluid flow circuit for the venting valve the following operation occurs. Energiration of solenoid M7 pushes pilot valve to the right and fluid from conduits 112i and 1% passes theretlnough into conduit 1193 and moves the venting valve to the right. As this occurs, fluid remaining in the cylinder 3% passes through conduits 4-5 and 176:, through valve i7 5 and into venting line 1%. At the same time pilot fluid on the right hand side of valve escapes through conduit 1%, valve and into vent line 1%. As will be understood, the venting of der 39 permits to move rapidly forward in cong'unction with the above described operation of the cable overtravel cylinder and to permit its dog to become disengaged from the car haul, the dog of the companion cylinder 38 meanwhile having been raised to car-engaging position.

The capacity of the accumulator dd need not be large since it normally is called upon to accept only excess fluid resulting from shock loadings upon the dogs of the apparatus.

Having thus described one embodiment of my invention and its operation, the several advantages of the same will be apparent to those skilled in the art. In particular, the safety and reliability of its operation while employing comparatively simple structure will be noted. The dog-actuating slide action, as well as the shift rod action, for example, are easily adjusted to provide for the switch and valve operation at the precise moments required. Moreover, merely by adjustment of the readily accessible strike members 23, 24, and 3%, Ta l, dogs also are actuated with a timing commensurate with these switch and valve operations. The dogs in their rearward movements, are preferably held down and in locked position until only a few inches before required engagement with the next car haul, thus reducing the danger of fouling on any improper car rigging.

.From the foregoing description of the invention it will be seen that various changes in the equipment described 1 1 may be made without parting from the scope or spirit of my invention; and it will be understood that the above description is considered to be illustrative of, rather tnan lim ting upon, the invention as defined by the appended claims.

What is claimed is:

1. A car-retarding apparatus comprising first and second elongated fluid motors each of which has a barney carried by a movable portion of the motor,

a car-retarding dog supported by said barney and pivotally mounted upon the movable portion of said motor and movable between car-engaging and cardisengaging positions,

a fluid system including a conduit interconnecting said motors whereby advancing movement of one motor causes fluid to pass through said conduit and to effect retracting movement of the other motor,

an over-travel fluid motor having a movable member and a sheave attached thereto,

a cable passing around said sheave and attached at its ends to the movable portions of said elongated motors,

a pressure fluid source having a conduit leading to a transfer valve movable between a first position supplying fiuid to said overtravel motor and a normal second position venting fluid from said overtravel motor,

means operable in dependence upon movement of said elongated motors for shifting said transfer valve between its first and second positions,

a venting valve in said fluid system movable between a normal first position blocking the venting of both of s id elongated fluid motors, a second position effecting venting of said first elongated motor, and a third position effecting venting of said second elongated motor,

means for replenishing said interconnecting conduit and compensating for fluid vented from said elongated motors during operation of said venting valve,

means operable independence upon the movement of said elongated motors for shifting said venting valve from its first position selectively to one of said second and third positions thereof depending upon the relative directions of movement of said elongated motors,

and longitudinally slidable means carried by the movable portions of each of said elongated motors for moving its respective dog to said car-disengaging position thereof concurrently with the movement of said transfer valve to supply fluid to said overtravel motor and with the movement of said venting valve to vent the motor associated with the dog eing so moved.

2. Apparatus as defined in claim 1 wherein said movable portions of said elongated motors comprise singleacting cylinders.

3. Apparatus as defined in claim 1 wherein said movable portions of said elongated motors comprise singleacting cylinders arranged in over-lapping longitudinal parallel relationship and with the barney of one motor being near the forward end of its cylinder and the barney of the other motor being near the rearward end of its cylinder thereby to provide a longitudinally compact apparatus.

4-. Apparatus as defined in claim 2 wherein said slidable means is longer than said cylinder and projects beyond the ends of said cylinder at all times' 5. A car-retarding apparatus comprising a framework mounting first and second elongated fluid motors in parallel relation to each other,

each of said elongated motors having a barney carried by a movable portion thereof, and a car-retarding dog supported by said barney and pivotally mounted upon the movable portion of said elongated motor for movement between car-engaging and car-disengaging positions,

a fluid system including a conduit interconnecting said elongated motors whereby advancing movement of one motor causes fluid to pass through said conduit and to effect retracting movement of the other motor,

an overtravel fluid motor having a movable member and a sheave attached thereto,

a cable passing around said sheave and attached at its ends to the movable portions of said elongated motors,

a pressure fluid source having a conduit leading to an electrically actuated transfer valve movable between a first position supplying fluid to said overtravel motor and a normal second position venting fluid from said overtravel motor,

an electrically actuated venting valve in said fluid system movable between a normal first position blocking the venting of both of said elongated motors, a second position effecting venting of said first elongated motor and a third position effecting venting of said second elongated motor,

electrical switching means operable in dependence upon movem nt of said elongated motors for shifting said transfer and said venting valves simultaneously,

means for replenishing said interconnecting conduit and compensating for fluid vented from said elongated motors during operation of said venting valve,

and longitudinally slidable means carried by the movable portions of each of said elongated motors for moving its respective dog to said car-disengaging position thereof concurrently with the movement of said transfer valve to supply fluid to said overtravel motor and with the movement of said venting valve to vent the motor associated with the dog being so moved.

6. Apparatus as defined in claim 5 wherein said switching means comprises first and second switches associated with each or" said first and second elongated motors and arranged for establishing a circuit to said electrically actuated valves only when the first switch for one of said elongated motors is actuated simultaneously with the actuation of the second switch for the other of said elongated motors.

7. Apparatus as defined in claim 6 including first and second slide rods positioned upon said framework slidably and mova le respectively with the movable portions of said first and second elongated motors for actuating said first and second switches for the respective motors as said portions respectively approach the limits of their forward and rearward movements.

8. In a longitudinally compact car-retarder having first and second movable single-acting, fluid operated cylinders arranged parallel to each other and adapted for reciprocable movement beneath a trip of cars,

each of said cylinders having a dog pivotally mounted thereon for movement between a raised car-engaging position and a lowered car-disengaging position,

a dog-actuating slide carried by each of said cylinders and longitudinally movable with respect thereto; said slide comprising,

a dog-lowering rod portion projecting beyond the forward end of said cylinder,

a dog-raising rod projecting beyond the rear end of said cylinder,

a entral slide portion attached to the inner ends of said rod portions to form a unitary slide therewith,

said central portion including a cam surface confronting the rear end of said cylinder and movable into and out of Contact with said dog,

said cam surface being movable into contact with said dog as said cylinder carries said dog-lowering portion into contact with a first strike member exterior of said cylinder and slide and being movable out of contact with said log as said cylinder carries said 13 dog-raising portion into contact with a second strike member exterior of said cylinder and said slide.

9. Apparatus as defined in claim 8 wherein the length of said slide is fixed and the positions of said first and second strike members are adjustable longitudinally of the axis of said slide thereby to modify the distance travelled by said cylinder between the dog-raising and dog-lowering actions of said slide.

14 10. Apparatus as defined in claim 8 wherein the dograising rod portion on said first cylinder is longer than the corresponding dog-raising portion on said second cylinder and said dog-lowering rod portion on said first cylinder is shorter than the corresponding dog-lowering rod portion on said second cylinder.

No references cited. 

1. A CAR-RETARDING APPARATUS COMPRISING FIRST AND SECOND ELONGATED FLUID MOTORS EACH OF WHICH HAS A BARNEY CARRIED BY A MOVABLE PORTION OF THE MOTOR, A CAR-RETARDING DOG SUPPORTED BY SAID BARNEY AND PIVOTALLY MOUNTED UPON THE MOVABLE PORTION OF SAID MOTOR AND MOVABLE BETWEEN CAR-ENGAGING AND CARDISENGAGING POSITIONS, A FLUID SYSTEM INCLUDING A CONDUIT INTERCONNECTING SAID MOTORS WHEREBY ADVANCING MOVEMENT OF ONE MOTOR CAUSES FLUID TO PASS THROUGH SAID CONDUIT AND TO EFFECT RETRACTING MOVEMENT OF THE OTHER MOTOR, AN OVERTRAVEL FLUID MOTOR HAVING A MOVABLE MEMBER AND A SHEAVE ATTACHED THERETO, A CABLE PASSING AROUND SAID SHEAVE AND ATTACHED AT ITS ENDS TO THE MOVABLE PORTIONS OF SAID ELONGATED MOTORS, A PRESSURE FLUID SOURCE HAVING A CONDUIT LEADING TO A TRANSFER VALVE MOVABLE BETWEEN A FIRST POSITION SUPPLYING FLUID TO SAID OVERTRAVEL MOTOR AND A NORMAL SECOND POSITION VENTING FLUID FROM SAID OVERTRAVEL MOTOR, MEANS OPERABLE IN DEPENDENCE UPON MOVEMENT OF SAID ELONGATED MOTORS FOR SHIFTING SAID TRANSFER VALVE BETWEEN ITS FIRST AND SECOND POSITIONS, A VENTING VALVE IN SAID FLUID SYSTEM MOVABLE BETWEEN A NORMAL FIRST POSITION BLOCKING THE VENTING OF BOTH OF SAID ELONGATED FLUID MOTORS, A SECOND POSITION EFFECTING VENTING OF SAID FIRST ELONGATED MOTOR, AND A THIRD POSITION EFFECTING VENTING OF SAID SECOND ELONGATED MOTOR, MEANS FOR REPLENISHING SAID INTERCONNECTING CONDUIT AND COMPENSATING FOR FLUID VENTED FROM SAID ELONGATED MOTORS DURING OPERATION OF SAID VENTING VALVE, MEANS OPERABLE IN DEPENDENCE UPON THE MOVEMENT OF SAID ELONGATED MOTORS FOR SHIFTING SAID VENTING VALVE FROM ITS FIRST POSITION SELECTIVELY TO ONE OF SAID SECOND AND THIRD POSITIONS THEREOF DEPENDING UPON THE RELATIVE DIRECTIONS OF MOVEMENT OF SAID ELONGATED MOTORS, AND LONGITUDINALLY SLIDABLE MEANS CARRIED BY THE MOVABLE PORTIONS OF EACH OF SAID ELONGATED MOTORS FOR MOVING ITS RESPECTIVE DOG TO SAID CAR-DISENGAGING POSITION THEREOF CONCURRENTLY WITH THE MOVEMENT OF SAID TRANSFER VALVE TO SUPPLY FLUID TO SAID OVERTRAVEL MOTOR AND WITH THE MOVEMENT OF SAID VENTING VALVE TO VENT THE MOTOR ASSOCIATED WITH THE DOG BEING SO MOVED. 